What infectious diseases are being reported in the parts of Japan you care about?
A city you would like to visit in Japan. A place you have traveled to before. An area where family or friends live.
This time, we are looking at provisional Infectious Disease Weekly Report (IDWR) surveillance data released by the Japan Institute for Health Security (JIHS) for September 7–13, 2026 (Week 37).
Explore infectious disease reports across Japan
Choose a disease and open a region or prefecture that interests you to see its figures. The map lets you switch between Japan as a whole, nine regions, and all 47 prefectures.
Why not take a look at a place you are curious about?
Reports across Japan for September 7–13
Across Japan, the number of reported cases per sentinel site during this week was 5.54 for influenza and 2.44 for COVID-19. Use the buttons on the card to see the other diseases.
“Cases per sentinel site” means the number of cases reported by each participating medical facility. It does not represent the total number of people infected in Japan.
What I noticed while making the map
The latest map shows several differences from the previous week. In Ibaraki Prefecture, influenza reports per sentinel site rose from 5.68 to 9.85. Nationwide, influenza also rose, from 3.29 to 5.54.
In Toyama Prefecture, COVID-19 rose from 2.06 to 4.38, while in Iwate Prefecture, hand, foot and mouth disease fell from 6.26 to 4.23.
Measles reports rose nationwide from 2 to 6, with 1 reported in Yamaguchi Prefecture and 5 in Fukuoka Prefecture. This continues to warrant attention.
From a city you would like to visit in Japan to somewhere you have been before, shall we explore together what is changing in the places that interest you?
Explore data for all infectious diseases (108 categories) →
Source: Japan Institute for Health Security (JIHS), “IDWR Provisional Data, Week 37, 2026” (published September 24, 2026; accessed September 25, 2026).
Sources for the comparison with the previous week: the official weekly case-count and sentinel surveillance CSV files for IDWR Provisional Data, Week 36, 2026 and Week 37.
- These figures are provisional and may be revised later. The Week 37 weekly report PDF had not yet been published at the time this article was prepared.
- Map colors show reporting patterns. They do not indicate an individual’s risk of infection or how safe an area is.
- For COVID-19, 2019 is not applicable; the 2021 figure covers notifications recorded in NESID under the mandatory reporting system for all diagnosed cases; and the 2026 figure is based on cases per sentinel site. Percentage changes across these years are not calculated.